With the continuing development of the LCD technology, the LCD with small size, low power consumption, no radiation and the like has gradually replaced the cathode ray tube (CRT) display, and becomes the mainstream product among display devices.
Nowadays, the LCD typically has a TFT array substrate structure as shown in FIG. 1. The TFT array substrate includes at least one sub-pixel region formed with a gate line (G) and a data line (D) intersected with each other (taking the structure schematic diagram of the TFT array substrate shown in FIG. 1 as an example, a sub-pixel region is formed when G1, G2, D1 and D2 are intersected with each other, and likewise, a sub-pixel region is formed as well when GN, GN+1, DN and DN+1 are intersected with each other.) The sub-pixel corresponding to each sub-pixel region comprises a transistor 11, a liquid crystal capacitor 12, and a storage capacitor 13. The gate of the transistor 11 is connected with a gate line, and the drain of the transistor 11 is connected with a data line; one end of the liquid crystal capacitor 12 is connected with the source of the transistor 11, and the other end of the liquid crystal capacitor 12 is connected with the output (denoted as ‘a’) of a reference voltage (Vcom); and one end of the storage capacitor 13 is connected with the source of the transistor 11, and the other end of the storage capacitor 13 is connected with the output of the reference voltage.
The sub-pixel region on which the transistor 11 is placed is activated for display when a driving voltage is loaded onto the transistor 11 through the data line.
Currently, in order to ensure the image continuity of each sub-pixel of the LCDs during the dynamic image display, the LCDs mostly change the driving voltage once per 60 Hz (i.e., the voltage conversion frequency is 60 Hz) to realize the AC drive of the sub-pixel. Even if each sub-pixel of the LCD is in the static image display, the voltage conversion frequency is fixed at 60 Hz.
However, since the LCD power consumption generated during driving each sub-pixel of the LCD for image display is proportional to the driving voltage, the voltage conversion frequency of the driving voltage, and the parasitic capacitance on the LCD data line, the LCD will produce high static power consumption because of the high voltage conversion frequency when each sub-pixel of the LCD is in the static display mode.